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The modeling of multivariate choice problems in the design of products within the framework of an information and software system is considered. The typical elements and functions of the information and software system of multivariate choice are given. Models of optimization problems of forming acceptable sets of alternative solutions when choosing analogs of parts and components are proposed. The formation of the initial set of alternative solutions is carried out on the basis of an assessment of the design, technological, electrical and operational characteristics of the alternatives of choice. The formalization of the problem of the final selection of the composition of parts and components according to technical and economic indicators is given. The proposed models are based on the use of Boolean variables describing the alternatives of choice. The structure of a specialized database of bath rooms for storing the characteristics of parts and components and the results of intermediate and final selection of design solutions is also given.

Development of test programs and analysis of the results of their execution is the basic approach to verification of microprocessors at the system level. There is a variety of methods for the automation of test generation, starting with the generation of random code and ending with directed model-based test generation. However, there is no cure-all method. In practice, combinations of various complementary techniques are used. Unfortunately, no solution for the integration of various test generation methods into a unified environment is currently available. To test a microprocessor, verification engineers are forced to use many different test generators, which results in a number of difficulties, such as (1) the necessity to ensure the compatibility of tool configurations (in each tool, a specific description of the target microprocessor is used, which leads to duplication of information); (2) the necessity to develop utilities for integration tools (different tools have different interfaces and use different data formats). This paper describes a concept of extensible environment for test program generation for microprocessors. This environment provides a unified approach for test generation; it supports widespread test generation techniques, and can be extended by new testing tools. The proposed concept was partially implemented in MicroTESK (Microprocessor T Esting and Specification Kit).

A strong influence of the counter-anions (such as Cl− and ClO42−) on the behavior of monolayers of an amphiphilic benzodithia-18-crown-6 butadienyl dye (dye 1) on aqueous subphases containing alkali metal or heavy metal cations (K+ or Hg2+) is demonstrated for the first time. Deduced from surface pressure–area and surface potential–area isotherms, reflection spectra and Brewster angle microscopy data, dye 1 monolayers show three types of structures depending on the counter-anion's influence on chromophore association and interactions with heavy and alkali metal cations.

New amphiphilic photochromic benzo-15(18)-crown-5(6) ethers (APC) differing in the position of the octadecyl substituent and the size of the crown cavity were synthesized. The compounds form stable monolayers in the air/water and air/alkaline metal salt solution interfaces. The results of the pressure isotherm measurements, atomic force microscopy (AFM), and electronic spectroscopy show that the structure of the monolayers formed depends on the structure of the parent APC and the nature of the cation in salt solutions. The area per molecule of APC in the monolayer (specific area) is the smallest on the water surface and increases by 20-40% on the aqueous subphase surface with an increasing concentration of salts therein to indicate the formation of APC complexes with the metal cations. When the hydrophobic aliphatic substituent is displaced from position 3 to position 5 of the benzothiazole ring, the specific area on the surface of water and subphases decreases twofold, which indicates the compactization of the monolayer on this modification. A reversible E-Z-photoisomerization of APC was found in the monolayers formed in the salt solution/air interface. The features of the reaction are defined by the specific organization of the amphiphilic molecules in the monolayer and by the nature of the cation.

Polymerase chain reaction (PCR) was used for detection of pathogenic Clostridium botulinum, Clostridium perfringens, Clostridium difficile, and Escherichia coli. With this aim in view, primers to botulinic toxins types A, B, C1, D, E, F, and G, perfringens enterotoxin, difficile toxin, and types 1 and 2 Shigella-like toxins were chosen and synthesized. Optimal amplification conditions were selected for each pair of primers, with DNA and the respective agent as the reaction mixture matrices. PCR was highly specific and sensitive in all cases. Its sensitivity was 10-100 cells/sample. Among the tested C. botulinum, C. perfringens, C. difficile, and E. coli strains, specific amplification products of expected size were observed only in the strains containing the respective toxin genes. These findings recommend the use of these methods in clinical microbiology. Strains containing type 2 Shigella-like toxin gene were detected among E. coli strains isolated from patients with the hemolytic uremic syndrome, which for the first time indicates that the problem with E. coli epidemic strain O157 is valid for Russia. As a result of our studies, test systems for detection of types A, B, C, D, E, F, and G C. botulinum strains, C. perfringens and C. difficile, and E. coli O157 strains are now available.

The effectiveness, both immunological (by an increase in the titers of antitoxins) and protective (by resistance to the inoculation of the absolute lethal dose of infective agents), of the regional (wound) revaccination with tetratoxoid (Clostridium perfringens, C. oedematiens, C. septicum, C. histolyticum) was demonstrated on the experimental model of wound infection (gas gangrene) of guinea pigs. The schedule of rapid immunization with tetratoxoid was developed, which made it possible to create good immunological preparedness (basic immunity) for subsequent revaccination in case of traumas within 6 days. The effectiveness of rapid immunization by the application of tetratoxoid on the wound was shown. This immunization ensured a considered increase in the titers of antitoxins within the first 6 days, which increased the protection of the animals from infection with each of the four causative agents of gas gangrene.

Preventive effects of artificial beta-carotene on the development of rat mammary gland adenocarcinomas induced by DMBA were studied in rats maintained on a diet containing beta-carotene at a dose of 2.5 mg per animal within 10 weeks, which was initiated after the carcinogen administration. The carotenoid treatment course caused the following effects: manifestation of adenocarcinomas induced by DMBA was decreased, latent period of neoplasm development as well as the rate of tumor differentiation were increased and metastatic spreading into the regional lymph nodes was inhibited.

Carcinogenesis in mice induced by the tryptophane derivative 3-hydroxyanthranilic acid was studied after administration of synthetic beta-carotene and ascorbic acid. The incidence of induced hemoblastoses and hepatomas was decreased 2-fold, while the latent period of their development was, increased in mice on a lifetime feed containing 15 mg/kg of beta-carotene. The anticarcinogenic effect of ascorbic acid added to drinking water was similar to that of beta-carotene. The additive inhibitory influence of beta-carotene and ascorbic acid on endogenous blastomogenesis was not found in mice.

The efficacy of eremomycin, a new glycopeptide antibiotic, was studied on a model of antibiotic-associated colitis in golden hamsters. The colitis was induced by intraperitoneal or intragastric administration of lincomycin. In a dose of 100 mg/kg administered orally once a day for 5 days eremomycin protected the animals from the lincomycin-induced colitis: some animals survived, the others died in later periods. When the animals were infected with a pathogenetic strain of Clostridium difficile followed by exposure to lincomycin the use of eremomycin produced the similar effect.

The study made with the use of complex methods established that the local (wound) application of tetanus toxoid rapidly made the manifestation of the lysosomal apparatus more pronounced, increased the oxidizing activity (determined in the nitro blue tetrazolium test) and phagocytic activity of the mononuclear phagocytizing system in the wound and in the regional lymph nodes. The wound application of tetanus toxoid significantly increased blast transformation of T lymphocytes in guinea pigs simultaneously with tetanus wound infection. The study confirmed the pathogenetic expediency of the proposed method for the stimulation of anti-tetanus immunity by the application of tetanus toxoid on the wound which specifically inhibited the primary stage of the infectious process.

Antibacterial activity of eremomycin, a novel glycopeptide antibiotic, against obligate anaerobic Gram-positive++ bacteria was studied. Eremomycin was shown to inhibit the growth of obligate anaerobic Gram-positive++ cocci and bacteria belonging to Clostridium in rather low concentrations and within narrow ranges of the MIC which was indicative of the antibiotic undoubted advantages. The antibacterial activity of eremomycin was 2 times as high as that of vancomycin and 8 times as high as that of ristomycin with respect to Gram-positive++ anaerobic cocci. Pathogenic strains of Clostridium spp. were 2 to 4 times more sensitive to eremomycin than to vancomycin. A significant property of the novel glycopeptide antibiotic was shown to be its capacity for inhibiting the growth of Gram-positive++ aerobic and obligate anaerobic cocci within the same concentration ranges which might be of importance in monotherapy of mixed aerobic and anaerobic infections.

A method for isolation of the ribosomal fraction (RF) from the cytoplasm of type-A C. perfringens strain BP6K was developed and its chemical and antigenic properties characterized. RF has been found to possess protective properties: two subcutaneous immunizations of mice with RF preparations adsorbed on Al(OH)3 in doses of 250 and 500 micrograms (dry weight) has ensured, on the average, the protection of 41.9% of the immunized animals from 1 DCL of type-A C. perfringens strain BP6K culture.

Sensitivity of the main microbial species causing gas gangrene to 21 antibacterial drugs was studied. The pathogens included 28 strains of Clostridium perfringens, 21 strains of C. oedematiens, 31 strains of C. septicum and 19 strains of C. histolyticum. Antibiotics having a bactericidal effect on the Clostridia were determined. The findings of the study were indicative of a variety of the antibiotic sensitivity spectra of the Clostridium spp., which accentuated the importance of antibiotic sensitivity assay in every particular case of gas gangrene.

1. The method of determining the width of normal cracks recommended in this article reflects adequately the specific characteristics of hydraulic-construction reinforced concrete, is based on experimental data, and can be used simultaneously with the procedure for crack width determination recommended in Chapter SNiP II–I, 14–69. 2. Test design using examples of reinforced-concrete members of structures at the Saratov and Ust'-Ilim hydroelectric plants, carried out by the new recommended procedure and by the procedure of Chapter SNiP II–I, 14–69, revealed that in many cases the use of the new procedure permits utilizing effectively high-strength Class A-III reinforcement, the design strength of which is 26% higher than that of the widely used Class A-II reinforcement. 3. It would be expedient to expand the production of Class A-III reinforcement to 60-mm-diameter bars.

Stimulation of the phrenic nerve evokes early (latent period 8–12 msec) and late (latent period 30–40 msec) surface-positive potentials in the contralateral sensomotor cortex. The early potentials arise in two localized areas of the posterior sigmoid gyrus — near the medial edge of the postcruciate dimple and near the lateral edge of the cruciate sulcus. The late potentials, on the other hand, are recorded not only over the whole surface of the posterior sigmoid gyrus, but also in the anterior sigmoid gyrus. The early component of the response is evidently evoked by stimulation of the first group of muscle afferents. Impulses reaching the cortex from the phrenic nerve may perhaps participate in the mechanism of the sensation of breathlessness.

The primary reason why hyperventilation is necessary in patients with paralysis of the respiratory muscles is insufficiency of the Hering-Breuer inhibitory reflex.

Hypercapnia in vagotomized cats can induce not only an increase in the depth of respiration, but also an increase in the frequency of inspiratory volleys. With deepening of anesthesia, the increase in depth of the inspiratory volleys continues, whereas the increase in the respiration rate disappears. These observations point to differences in the central mechanisms controlling the frequency and depth of respiration, of which the former is more susceptible to suprabulbar influences.

To maintain a normal arterial pCO2 in phrenicotomized rabbits artificial ventilation of the lungs must be increased to almost double the normal level. The reason is that phrenicotomy causes a decrease not only in pulmonary, but also in alveolar ventilation.

Transplacental administration of tyrosine metabolite p-hydroxyphenyl lactic acid having blastomogenic activity induced development of malignant and benign neoplasms (leukemias and lymphosarcomas, adenomas and pulmonary carcinoma, hepatomas, papillomas, and cancer of the urinary bladder and other tumours) in progeny of CC57BR and C57BL mouse strains, in 88 and 78% of cases, respectively. The number of neoplasms was significantly higher, than in the control, they appeared earlier and were of more malignant character. The role of endogenous blastomogenic substances in the development of leukemias in the newborn and yound children is discussed.

The results of the studies on development of a rapid assay of antibiotic sensitivity of gas gangrene causative agents with their high nutrient requirements under obligatory anaerobiosis are summarized. The data on development of a uniform standard nutrient medium with the use of dry components made in the USSR are presented for the first time. The medium is intended for rapid assay of antibiotic sensitivity of the main causative agents of gas gangrene, i.e. C. perfringens, C. oedematiens, C. histolyticum and C. septicum.

The cellular and antigenic interrelations within each Clostridium species have been studied with a view to the selection of strains for the preparation of specific rabbit antisera possessing a wide serological spectrum of action within the species. The indirect immunofluorescence test making it possible to determine the species of clostridia in native pathological material from wounds or in cultures, subjected to short-term incubation, within 1-1.5 hours has been developed. This test can be used in laboratory practice for the diagnosis of gas gangrene in humans, as well as for the identification of pathogenic clostridia.

Morphological studies carried out in the igated loop of the rabbit small intestine, used as a model, have revealed that the action of the enterotoxins of C. perfringens type A reference strain and C. perfringens type A strains isolated in the USSR on the intestinal mucosa is absolutely identical. This action is manifested by the destruction of epithelial cells on the tops of the villi, inflammatory infiltration and considerable exudation of fluid into the lumen of the intestinal loop. Early lesions of the brush border of enterocytes, accompanied by the loss of alkaline phosphatase activity and the disappearance of the glycocalix, have-been histochemically established. C. perfrinegens antienterotoxic serum has proved to be capable of completely neutralizing the histopathological activity of C. perfringens enterotoxin.

Erythrocytic immunoglobulin diagnostic reagent for detecting Cl. perfringens enterotoxin in the indirect hemagglutination test has been obtained. The diagnostic reagent has been prepared on the basis of antibodies of Cl. perfringens enterotoxin with the use of acroleinized tanned sheep red blood cells. The indirect hemagglutination test with this reagent is characterized by high specificity and sensitivity (the method permits to detect enterotoxin protein at a concentration of up to 0.005 microgram/ml). The preparation thus obtained is stable and ensures highly reproducible results.

A considerable blastogenic activity of biogenic methoxyindoles--melatonin, 5-methoxytryptamine (5-MOT) and their common metabolite--5-methoxyindolyl-3-acetic acid (5-MIAA) was established by prolonged s.c. injection in C57BL/6 mice. However, the blastogenic effect of 5-MOT decreased by 26% when its further metabolism to 5-MIAA was blocked for some time and the synthesis of its carcinogenic metabolite was inhibited. These results showed that the blastogenic effect of 5-MOT is not direct; and it is mediated by its transformation to 5-MIAA in the body.

An express method for determination of antibiotic sensitivity in the strains of Cl. perfringens of type A using Soviet dry nutrient media and antibiotics is proposed. The criteria for estimation of the level of the antibiotic sensitivity of the causative agent of gas gangrene in short periods on the basis of comparison of the data of the antibiotic agar diffusion procedure and the antibiotic MIC were worked out. Twelve antibiotics and 45 collection strains of Cl. perfringens of type A were used in the experiment. The antibiotic agar diffusion method with the use of the nutrient media, microbial load and cultivation conditions developed by the authors is recommended for tentative determination of the antibiotic sensitivity in Cl. perfringens of type A for 4 hours. The use of the agar diffusion method and determination of the antibiotic MIC provided complete estimation of tha antibiotic sensitivity of Cl. perfringens of type A within not more than 24 hours.

Daily urinary excretion of 5-hydroxy-3-indoleacetic acid (5-HIAA) and 5-methoxyindole-3-acetic acid (5-MIAA) was studied by chromatography-mass-spectrometry in patients with cancer and healthy subjects. A considerable increase in urinary 5-MIAA-excretion was shown in patients with cancer of the stomach, rectum and lung. In some cases, a correlation was found between high urine levels of carcinogenic 5-MIAA and similarly high levels of 5-HIAA excretion with urine.

The immunomorphological reaction of regional lymphoid organs, the pathomorphology of wound tissues, humoral antitoxic response and a protective effect after local (wound) booster immunization with tetanus toxoid have been studied in observations on 100 guinea pigs with experimental wound infection. The study has shown that the local application of tetanus toxoid, besides stimulating humoral response, induces a more rapid effect aimed at the primary elements of the infectious process (the germination of spores, the adhesion, colonization and toxin formation of the causative agent), thus facilitating the localization of the focus of infection, the development of reparative processes in the wound and the arresting of the infection.

Guinea-pigs were immunized with anatheta-hemolysin preparations adsorbed on aluminum hydroxide, as well as with the mixture of anatheta-hemolysin and type A Cl. perfringens toxoid, purified and concentrated. Anatheta hemolysin preparations were obtained with the use of homogeneous theta hemolysin, as well theta hemolysin of various purification degrees. As a result, antatheta hemolytic guinea-pig sera capable of neutralizing 2,000-8,000 HU of theta-hemolysin were obtained. Tests made to establish the degree of protection in the immunized guinea-pigs did not show that the animals immunized with the mixture of anatheta-hemolysin and type A Cl. perfringens toxoid, purified and concentrated, had any advantages in the degree of protection over the animals immunized with the toxoid alone. But there is no doubt that this component plays a positive role under the conditions of natural gas gangrene when the hemolytic action of Cl. perfringens toxin becomes considerably pronounced.

Injection of subconvulsive doses of strychnine blocking the inhibitory synapses significantly increases the reflex activity of the respiratory muscle evoked by stimulation of the sciatic nerve as well as by inhalation of hypercapnic gas mixture. Thus the inhibitory synapses prevent the extreme hypocapnia evoked by hyperventilation.

Electrical stimulation of the phrenic nerve gives rise to early (with latency of 8--12 msec) and late (with latency of 30--40 msec) surface-positive potentials in the contralateral sensory-motor cortex of cats. The early potentials occur only in two discrete areas of the rostral part of the posterior sigmoid gyrus: just rostromedial to the post-cruciate dimple and at the lateral tip of the cruciate sulcus. In contrast to the early potentials, the late ones can be recorded not only from the whole surface of the posterior sigmoid gyrus but also from the anterior sigmoid gyrus. The early potentials presumably appear on stimulation of group I muscle afferents. It is possible that impulses reaching the cerebral cortex from the phrenic nerve participate in provocation of the sensation of breathlessness.

For the first time in the USSR, as a result of all-around analysis of the problems connected with tetanus prophylaxis under conditions of the Arkhangelsk region the authors conducted a trial on the suspension of the use of antitetanus serum in trauma. Besides the elimination of the population allergization, replacement of the antitetanus serum with the toxioid facilitated the emergency prophylaxis of tetanus, created prerequisites for the immunity maintenance at the protective level in the population, and served as the necessary stage along the route of further improvement of emergency prophylaxis and elimination of tetanus.

The use of antitetanus serum (ATS) in the north taiga soil-vegetative zone and farther to the north is inexpedient because of an insignificant contamination of soil with B. tetani and a trivial contact of the population with soil. In the Arkhangelsk region with a high incidence of trauma and a low tetanus morbidity the damage caused to the population by the administration of ATS in the form of serum sickness (1.1% of the persons given ATS injections) and anaphylactic shock considerably exceeded the value of negative results of the infection. In the presence of immune population (over 86% of the children and 82% of adults are immune) and with additional vaccination of definite groups it is not only possible, but necessary to suspend ATS injections in trauma; instead, 0.5 ml of tetanus toxoid should be used for revaccination. Suspension of ATS application in trauma gives marked economy of the budget of the public health of the region.